An apparatus to cut free flank bones of beheaded, slaughtered fish, which preferably have opened abdominal cavities and are transported tail-first in transport direction T with their backbone resting on transport saddles, includes: an upper bone guide to guide the backbone from the dorsal side; a lower bone guide to guide ventral spokes of the fish, which spokes are formed in the region from the tail to the abdominal cavity; and a separating unit for detaching fillets from the flank bones surrounding the abdominal cavity. The separating unit includes a separating means having a corresponding counter unit and can be brought from a standby into a working position and vice versa. A detaching device is located in the upper bone guide region to loosen the bone connection between the flank bones and backbone of at least some of the flank bones. A corresponding filleting machine and method are provided.

A fish sedation device that reliably energizes and sedates fish and enables a slaughter operation to be satisfactorily performed by energizing fish on a mat from electrodes via high resistance water which has a higher electrical resistance than that of the fish.